Method of softening water.



K. SCHREIVIPP. METHOD" 0F soFTENlNG WATER.

APPLICATION FILED FEB. 7. 1914.

g; 393%?0 Emma. May 11, w15.

2 SHEETS-SHEET I.

naar'. sonner/rrr, or KARLSRUHE, enumerar.

'.llE'llOD' GF SOFTENING WATER.

Specification of Letters atent.

Patented May itl, Milli Application filed February 7, 1914. Serial No. 17,13?.

T @ZZ @ehem it may concern Be it known that l, KARL Sonurtrrr, residing at Karlsruhe7 in the Grand Duchy of Baden and Empire of Germany', have invented certain new and useful mproveinents in Methods of Soittening Weten of which the 'following is speciiication.

This invention relates to a process for totally or partially removing the hardness of water, resulting from the content of carbonatos. As is known a distinction is made between such substances which give the Water a temporary hardness and such that give it a permanent one. The temporary hardness is produced chiefly by the bicarbonates of lime and of magnesia, and such y hardness yis frequently termed carbonate hardness.v4 I

The present method dispenses with the addition of chemicals to the Water, the formation of the insoluble carbonates, z'. e. the softening of the Water, being elected in quite a different manner.

l have found that if Water containing the soluble bicarbonates is kept heated for some time at a temperature above the boiling point, and then a sudden relief of pressure is edected, the dissolved bicarbonates become decomposed and the carbonatos separate forming a compact precipitate. An important feature of this novel method resides obviously in the difference of pressure eiected by the sudden relief-o1 pressure7 and, in fact, experience has shown that the higher that difference of pressure, or that tall of pressure, is, the more perfect is the sotteningl of A the Water.

chosen 'to produce this difference orf pressure.

The Water may, as already i'nentioncd, be heated to a temperature above the boiling point, z'. e. it may besubjected to a pressure corresponding to the high temperature applied, and may then be made to pass as quickly as possible into another receptacle,

Where there is atmospheric pressure only,

whereby the corresponding considerable fall of pressure entails the precipitation of the insoluble carbonatos in a state permitting of their easy separation by iiltration. 0r the Water is heated to a temperature below the boiling point and the difference of pressure is produced by quickly conducting the thus treated Water into a receptacle where there is an appropriate partial vacuum, Or the 'Various ways may be Water is heated to any predetermined temperature, and a pressure which is higher than that corresponding to the temperature of that Water is exerted upon the .vater by any mechanicall means, the relief ci" the pressure, or an appropriately `lower pressure, being then produced by suddenly re,

. moving that higher pressure from the water.

Water is, and the greater the contents of.

fixed carbonio acid, the greater must be the diderence of pressure produced by thessudden relief of pressure, which is, in many cases, equivalent to a correspondingly higher heating of the Water to be treated. Experiments have further shown that, at a low pressure and a loW temperature, bicarbonate of lime may be more completely decomposed than the bicarbonate of magnesia. if? thus, a Water to be softened has7 proportionately. a greater content of said latter bicarbonate; the softening must be effected at a corre-I spondingly higher temperature and higher pressure. The suitable treatment of the water thus depends in some cases upon the nature and the character of the temporary hardness.

ln the accompanying d anfings l have shown several forms of apparatus by means of which my invention may be practised.

Figure l is a schematic View pa section of an apparatus 'wherein the n er is heated above the boiling` point and is then passed into a vessel under atmospheric pres sure. Fig. 2 is ay similar view of an apparatus 1ivherein the water is heated in one vessel to a. temperature below boiling point and is then passed into a vessel wherein a partial vacuum prevails. Fig. 3 is a similar View of an apparatus wherein the Water is heated in one vessel to any desired temper; ture, pressure is applied thereto, and the Water is then passed into a vessel wherein atmospheric pressure prevails; and Fig. /lis a similar view of apparatus wherein the water is preliminarily compressed,

heated,iand then passed into a vessel where-- in atmospheric pressure prevails.

Referring to the form of invention shown in Fig. l, the numeral 10 denotes a heating vessel containing the worm 11 by means of Which the water may be heated to a tem-` perature above the boiling point. 12 denotes a vessel open to: atmosphere andconnected by the pipe 13 with the vessel 10. The pipef13 is provided with the controlling valves 14, and the vessel 12'is provided y with the draw-oit cock 15; AIn this form of invention the Water `in vessel v10 is heated to a temperature abovethe boilingppoint, and then by opening the valves 14.L the wa' ter ispermitted t0 suddenly rush into thev vvessel 12-so that the* pressure which actedi upon the Water in vessel 1Q is suddenly rey lieved when the water reaches the vessel 12.

' *In4 Fig. 2,10?? denotes the heating vessel provided lwith the heating Worm 11, and

r12EL denotes the chamber into which the Wa- `ter flows from" thevessel a through the pipe 13#1 which vis `controlledby the valves '14?'. 16 is a pipe leading .from the vessel 12?* to a pump 17 adapted to produce a par- `tialvvacuum in the vessel 12a. The water invvvessel 10a"is heated'to'i`a` temperature belol-w the boiling point, and 'after a sufficient vacuum has been created in the vessel 12a by the' pump 17, the valves ,14al are opened to permit' the sudden flow of-Water from 10a to 12a, thereby providing for the pressure differential above .referred to.

Referring to the constructionof Fig.. 3, 10b denotes the heating vessel provided with the heating worm 11F. 18 denotes a pipe connection between the vessel 10b.l and the vessel 12b, a pressure pump 17b being Ainterposed in this pipe connection, A .throttle valve 19 is also interposed in the pipe connection. The Water in the vessel 10b is heated to any desired predetermined tempera* ture, say 150 C. Then the water has lieved. lAssuming that the water is under a pressure of 4; atmospheres in the vessel 10b, and that the pump 17b further com'- presses the water to 10 atmospheres,'it will be obvious that when the water passes through the throttle valve 19- into the vessel 12b, there will be a very substantial relief of` I'nvthe construction of 4, 17c is ai pump connected by a pipe y20 to the heat ing vessel l0, the latter being connected to the vessel '12 bythe pipe 13c controlled by the' valve 1.4. Within the pipe l0-is the' heating 'coil 11, In this form of the invention thev operation is I.as followsz-Before the water enters the vessel 10 it is compressed by they pump 17c to, say,v 4 atmospheres. The Water then passes' into the vessel 10c `and'is there heated `to a temperature which is lower than that which would correspond to a pressure of 4 atmospheres, in

yorder that the water may not boil. 'From the vessel 10c the water is permitted to pass through the pipe 13c into` the vessel .12c

which is open to atmosphere, and in this v manner the sudden pressure dierential is secured. f

It will'` be noted that in each form of ldevice above referred to,` the water is first heated to a predetermined temperature,` and is thereafterpermitted to pass intofa vessel inl which the pressure either` due entirely tov heating or otherwise produced, issuddenl) r'eliev d.

" Having now described my invention, I declare that whatl I claim is:

The herein describedmethod ofsoften? ing Wate l which consists in subjecting the Water to pressure by heating the same in a chamber, and thereafter suddenlymelieving the pressure on the water byv passing the latter into a chamber whereinthe pressure is considerably lower than in the vfirst mentioned chamber, whereby insoluble carbonates are precipitated-in said second chamber.

In testimony whereof I afix my Asignature in prcsenceeoi two Witnesses.

KAl{L /SCHR'EMPP- Witnesses :l y

HEINRICH LIMrrlwI-N, S. S. BERGER. 

